Thank you very much for your comments!

1. Small 10A relays. They click too, but they are much quieter.
However, I don't know if the contacts can stand the inrush current. I
bought 3-pole relays and connected the poles in parallel, so that
gives me 30A in theory. Is this a good idea?

No. Fractional variations in contact resistance will cause drastic
current imbalances, and generally speaking, it buys you little.

This may be truly overkill, but I did a quick calculation of the
effects
of the variation of resistivity with temperature. The idea is that
if there is an imbalance, the pole carrying more current will heat up
more, and the resistance will increase relatively to the other poles,
equalizing the currents.

For common metals (Al, Cu, Fe) relative-delta(R) = alpha * delta(T)
with alpha approximately 0.4 * 10^-3 near room temperature.
That means that a temperature increase of 25C causes a 10%
increase in resistance. I measured the contact resistance in
my relay, it appears to be only 7 mOhm with 1A current, and
the variation between the poles is about 10%. So I don't think
I need to worry about that kind of temperature difference.
Things could change at higher temperature, but alpha
also increases (it's a function of some power of T greater
than 1) and that should help equalize the currents.

If there is a flaw in this reasoning I will sure be glad
to know before I fry my relay!